class_docstr: Checker with methods for validate data related options.
code: def _validate_source_features_opts(cls, opt):
      if opt.src_feats_defaults is not None:
          assert opt.n_src_feats == len(
              opt.src_feats_defaults.split("￨")
          ), "The number source features defaults does not match \
                  -n_src_feats"
  
imports: import configargparse
  import os
  import torch
  import onmt.opts
  from onmt.utils.logging import logger
  from onmt.constants import CorpusName, ModelTask
  from onmt.transforms import AVAILABLE_TRANSFORMS
label_desc: Use image node_id 8 for calling the DataOptsCheckerMixin obj's underlying member method code with example usage: obj._validate_source_features_opts(cls, opt) without return types